Tube end structure



July 6, 1937. H, LlNDAg 2,086,276

TUBE END STRUCTURE Filed April ll, 1934 INVENTOR flenryEZZnda ATTORNEYSPatented July 6, 1937 UNE'BED STATES FATENT GFFIQE TUBE END STRUCTURE 2Claims.

The present invention relates to an end structure for an inflatabletube, such as a core, for use in making concrete conduit.

In the malnng of concrete conduit, as set forth in my application,Serial Number 603,138 (in which application this invention isessentially disclosed, but not claimed), it is sometimes desirable tocouple several lengths of core together and to use them when thuscoupled as a single unit, and it is also necessary to have a convenientthreaded end portion to facilitate the attachment of a pump to an end ofthe core,

and a cap, or other suitable closure member, for

the other end of the core.

Among the objects of the present invention is to secure an end fittingfor the conduit core which will be particularly water and air tight,which shall be strengthened and reinforced to resist to the extreme thepulling stresses exerted in removal of the core, and which will besimple and easy of repair.

In order to attain these objects, there is provided, in the adaptationof my invention shown in the drawing, a tubular member projecting at oneend into one end of the core, the tubular member having an enlargedinner end over which the end of the core is drawn inwardly and ligatedto the tube. In the adaptation shown in the drawing, I provide a sleevesurrounding the core 30 and fitting exteriorly at its inner end over thecore, with sealing elements filling the spaces between the sleeve andthe ligated end of the core, and the core and inner enlarged end of thetube. The sleeve has threaded support upon the 35 tube so as to beadapted to be forced into close contact with the core and with thecontained sealing elements to bring about a close sealing engagement ofall the component parts.

These and other features of the invention will 40 be more fully broughtout in the following description and the accompanying drawing, whereReferring to the drawing in detail, a tubular concrete conduit core I ispreferably of the type 55 shown in my allowed application, Serial Number603,138, although the end fitting comprising the present invention issuitable for any inflatable tubular member of a general characterrequiring an end fitting of this type. The end fitting comprises atubular, central member 2 having a threaded portion 3 in the outer endthereof, and having a head portion such as a disk i secured to the innerend thereof, as by riveting 5.

The periphery of the head G is preferably tapered, as shown at 6. Thisangle is not critical, but should be such as to permit the disk l to bedrawn along the inner face of the conduit I without cutting into therubber or fabric with which such conduits are usually lined.

A filler ring 8, of rubber, is provided on the outer face of the disk 4,this ring being preferably formed of a waterproof substance, such asrubber. The end of the core I is drawn inwardly as by means of a suturering 9 into close engagement with the tube 2, and a filler it], also,preferably, of plastic, waterproof substance, is provided over thesuture ring 9 and end portion of the core l. A cap H has the outer endportion l2 thereof of a size to telescopically receive the tube 2therein, and is provided with an out-.- wardly fiaring skirt is adaptedto fit closely over the filler it and to grip the walls of the core Ibetween the disk 4 and the inner end of the cap 1 l. A nut M is threadedonto the threaded end portion 3 of the tube 2, and engages the outer endof the cap member ll, forcingthe member ll inwardly to compress thefiller Hi and force the inner end portion of the cap member ll intoclose gripping engagement with the wall of the core l. After assembly,the structure may be subjected to heat treatment to completevulcanization of the elements 8 and Hi when these elements are ofunvulcanized, or partially vulcanized, rubber.

The device comprises a simple and strong end connection for conduitcores, and one which is peculiarly adapted to the severe end stresses towhich such fittings are subjected in drawing a long length of core froma formed conduit. The

entire structure may be disassembled and re-l moved from the core, ifnecessary or desired,

and this feature is particularly valuable, where a it is necessary tocut or change the length of conduits in the field. By the use of anordinary pipe union, not shown, but with which those versed in the artare familiar, several lengths of conduit can be connected together, asshown in my pending application, Serial Number 603,138,

where it is desired to use a plurality of lengths of core, as a singleunit.

An ordinary pipe cap, also not shown, since such caps are well known tothe trade, may be threaded onto the threaded portion 3 of the tube 2where such closure is necessary.

While I have, as set forth, constructed the sealing ring 8 and thesealing filler I0 of plastic, unvulcanized, or partially vulcanizedrubber, I may, particularly with respect to the ring 8, construct thesame of other suitable material, such as lead or copper, and may makethe sleeve 8 a component part of the enlarged end of the tube 2.

I claim:

1. In combination witha core, a core head of the class describedcomprising a tube having one end projecting into the end of the core,said tube being provided with a circumferentially enlarged end portionover which the end of the core is drawn and turned inwardly into contactwith the tube, a sleeve adjustably' supported on the tube to makeexterior contact with the core, and a sealing element filling the spacebetween the sleeve and the end of the core surrounding the tube, withsaid sealing element forming a tapering wedge between the sleeve and thecore end.

2. In combination with a core, a core head of the class describedcomprising in combination with the end of the core a tube having one endextending into the end of the core, saidextending tube end having anoutwardly projecting part, means for clamping the end of the core aroundsaid tube on the outer side of said pro- 7 jecting part, a sleeveadjustably supported upon

